The Handbook of Radiotherapy Planning covers essential concepts and practical considerations for achieving high-quality external beam radiotherapy plans. Edited by recognized experts and authored by highly skilled planners, this concise guide emphasizes plan quality as a critical clinical skill. It bridges the gap between standard reference materials and day-to-day clinical practice by providing anatomical site-specific guidelines, planning tips, real world examples, and advanced topics. Each chapter highlights decision-making processes, common pitfalls, and techniques to improve consistency and quality across a variety of disease sites and treatment approaches. The book fosters collaborative workflows and promotes a deeper understanding of treatment planning beyond minimum standards. This book is intended for physicists, dosimetrists, and radiation oncologists who seek practical and high-yield guidance in radiotherapy planning, particularly those building their skills early in their careers.